OBJECTIVE/WARM-UP Students will be able to distinguish between accuracy and precision. Students will be able to use scientific notation. How many sig figs in each number?

NOTES-ACCURACY Word/Phrase:Definition: Hints or diagram:Meaning in My own words: accuracy How close the measurement is to the real, true, or correct value correctness

NOTES-PRECISION Word/Phrase:Definition: Hints or diagram:Meaning in My own words: precisionHow close measurements are to each other repeatable

On the TV show “The Biggest Loser”, weight loss is reported in whole pounds, but percentage weight loss is given with two decimal places. For example, if a 210 lb. person lost 4 pounds, the percent weight loss is reported as 1.90% weight loss. Write a letter to the producers of the show to explain how this is unfair and not correct precision in reporting the percentage weight loss. Suggest a way to correct this for future shows.

Scientific Notation A short-hand way of writing large numbers without writing all of the zeros.

The Distance From the Sun to the Earth 93,000,000

Large Numbers

Step 1 Move decimal left Leave only one number in front of decimal

Step 2 Write number without zeros

Step 3 Count how many places you moved decimal Make that your power of ten

The power of ten is 7 because the decimal moved 7 places.

93,000, Standard Form 9.3 x Scientific Notation

Practice Problem 1) 98,500,000 = 9.85 x 10 ? 2) 64,100,000,000 = 6.41 x 10 ? 3) 279,000,000 = 2.79 x 10 ? 4) 4,200,000 = 4.2 x 10 ? Write in scientific notation. Decide the power of ten x x x x 10 6

More Practice Problems 1) 734,000,000 = ______ x ) 870,000,000,000 = ______x ) 90,000,000,000 = _____ x On these, decide where the decimal will be moved. 1)7.34 x ) 8.7 x ) 9 x 10 10

Complete Practice Problems 1) 50,000 2) 7,200,000 3) 802,000,000,000 Write in scientific notation. 1) 5 x ) 7.2 x ) 8.02 x 10 11

Scientific Notation to Standard Form Move the decimal to the right 3.4 x 10 5 in scientific notation 340,000 in standard form move the decimal

Write in Standard Form 6.27 x x ,270,000 90,100

Small Numbers

Step 1 Move decimal right Leave only one number in front of decimal

Step 2 Write number without zeros

Step 3 Count how many places you moved decimal Make that your power of ten

The power of ten is -4 because the decimal moved 4 places.

Standard Form 3.24 x Scientific Notation

Practice Problem 1) = 9.85 x 10 ? 2) = 6.41 x 10 ? 3) 2.79 = 2.79 x 10 ? 4) = 4.2 x 10 ? Write in scientific notation. Decide the power of ten x x x x 10 -2

Complete Practice Problems 1) ) ) Write in scientific notation. 1) 5 x ) 7.2 x ) 8.02 x 10 -4

Scientific Notation to Standard Form Move the decimal to the left 3.4 x in scientific notation in standard form move the decimal

Write in Standard Form 6.27 x x

Scientific Notation Examples Change from scientific notation a) the distance from Pluto to the Sun is 5.9×10 12 meters b) the Milky Way disk radius is 3.9×10 20 meters. c) The speed of light is 3 x 10 8 meters/second. d) the sun is 1.5x meters from earth e) Mass of proton : x kg f) Mass of neutron: x kg g) Mass of electron: × kg Change into scientific notation h) kg. is the mass of a dust particle! i) A proton has a diameter of approximately mm

Quick Review When adding or subtracting: Make sure the exponents are the same and line up the decimal points. When multiplying: Add the exponents When dividing: Subtract the exponents